well i have had the new diff in my car and it looks very good once again.
It took three practice runs, after that two qualifiers and two a-mains in the clubrace last weekend. the track was a bit muddy from the rain. it was dry but the rain usually washes some dirt on the track. so i was expecting to have the diff needing to be replaced quick. after every run i have checked it and it was okay so i continued.
so now it took 7runs and it still feels good. now it feels like the old diff after a rebuild so still fine for a few more runs